I don't know about other areas in Bolivia, but I am based in Santa Cruz. We have been told that crime has gotten much, much worse over the last few years. I think as long as you are sensible you will hopefully be ok, but the risk is always there, especially as an ex-pat or foreign national. The latest biggie here is people dressing up as police and pulling you over then holding you up - you always have to have your wits about you here. It makes for interesting living ;) I would have loved to have said no, but anyone saying that is lying.